Field
Exemplary embodiments relate to a touch sensor and a method of manufacturing the same, and more particularly, to a touch sensor including metal nanowire and a method of manufacturing the same.
Discussion of the Background
Display devices, such as a liquid crystal display (LCD), an organic light emitting display (OLED), and an electrophoretic display (EPD), portable transmission devices, and other information processing devices, and the like, may perform a function through an input from various input devices. Recently, an input device including a touch sensing function has been used as the input device.
The touch sensing function may sense a change in pressure, charge, light, and the like, applied to a screen of a display device, to detect an object's approach or contact to the screen, or contact position information, which may occur when the object, such as a user's finger, a touch pen, or the like, approaches or contacts the screen to write characters or draw pictures. The display device may receive an image signal and display an image, based on the contact information.
The touch sensing function may be implemented by a touch sensor. The touch sensor may be classified into various touch sensing types, such as a resistive type, a capacitive type, an electromagnetic resonance type (EMR), and an optical type.
Generally, the resistive type and the capacitive type have been mainly used. In the resistive type touch sensor, two spaced apart electrodes, which face each other, may contact each other by a pressure applied from external objects. When the two electrodes contact each other, a resistance thereof may be changed. As such, contact positions, and the like, may be detected by recognizing a change in voltage at the contact position.
The capacitive type touch sensor may include a sensing capacitor formed of a sensing electrode. The sensing electrode may transfer a sensing signal and sense a change in capacitance of the sensing capacitor, which may be generated when conductors, such as a finger, approach the sensor, to detect a touch in the touch screen, touched positions, and the like. The capacitive type touch sensor may sense a touch when the user or a conductive object touches the touch screen.
A flexible electronic device may include a touch screen. Due to flexible characteristics of the flexible electronic device, an electrode of the touch screen may also be flexible to prevent occurrence of defects. As a material of the electrode having flexibility, various materials, such as metal nanowire, for example, silver nanowire (AgNW), etc., carbon nanotube (CNT), graphene, metal mesh, and conductive polymer have been researched. Since these materials may have low conductivity, low resistance metals, such as copper, may be used to supplement conductivity of a wiring part of the touch screen. However, the low resistance metal such as copper may have low flexibility and be easily oxidized, thereby generating corrosion therein. The corrosion of the low resistance metal may be spread to the entire touch screen, which may deteriorate reliability of the touch screen.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.